There are six data collection points in the cascade of procedures: (1) a baseline telephone assessment, (2) a post-baseline assessment that can be completed online or by telephone, (3) a clinic visit assessment, (4) a telephone call following mailing of results, (5) a six month follow-up telephone assessment, and (6) abstraction of automated medical records to assess health care utilization and health care seeking outcomes. Enrollees are being identified from those who receive care at ten clinics within the Henry Ford Health System (HFHS). Identified potential participants are mailed a letter from HFHS describing the study and requesting their participation in the baseline assessment. Interviews are conducted by a trained survey interviewer at the Center for Health Studies (CHS) in Seattle. Following the baseline assessment, participants who are eligible are sent information about multiplex genetic testing and encouraged to visit the Web site and participate in an on-line decision process assessment for a $50 incentive. As part of their experience, individuals are asked to consider having the Multiplex Genetic Susceptibility Test. Test results of genetic variations that confer an increased risk for disease are communicated by NHGRI directly to participants through the mail. Results are not given to health-care providers or included in medical records. A HFHS research educator attempts to contact participants by telephone as soon after they have received their test results as possible, preferably within ten days of receipt of mailed results (depending on the availability of the participant). The research educator offers assistance in interpreting the test results as well as the option to consider other preventive health resources available to HFHS members. The Bioinformatics and Scientific Programming Core (led by Dr. Andy Baxevanis) has taken primary responsibility for all computational- and IT-related aspects of the Multiplex Initiative. This has included developing data specifications and data transfer protocols involving NHGRI, HFHS, CHS, and the Center for Inherited Disease Research (CIDR) in Baltimore. These data transfer protocols track each step that a study participant experiences as part of this study. These data transfers are critical, since they serve as event triggers during the study and ensure that a study subject (and their biological samples) move smoothly through the data collection pipeline. The data themselves are incredibly disparate in nature and include the results of baseline interviews, information on study subject enrollment, the tracking of blood draws, the location of samples at any given time, responses to on-line and in-person surveys conducted by CHS, relevant clinical data from HFHS, genotyping data from CIDR, the status of mailing result booklets, and the status of follow-up visits. We have spent a significant amount of time modifying LabMatrix, NHGRIs clinical database system, to accommodate these data as they arrive at specified intervals, as well as to be able to automatically generate result booklets for mailing to study participants. Since LabMatrix will be the storehouse for all Multiplex Initiative data, we have given significant consideration to ensuring that LabMatrix can also be used as an analysis tool downstream, enabling investigators who wish to perform secondary analyses on these data to easily amass and interrogate custom data sets. As part of the data collection pipeline, they have also spent a significant amount of time developing the Multiplex Initiative Web site (http://multiplex.nih.gov). This Web site is the studys primary tool for collecting survey information and has been designed so that each participants visit to the site can be precisely tracked, down to the amount of time spent on each page and the order of links that were selected;these data are important for answering some of the studys behaviorally related questions.